Observations on the fishery and biology of Megalaspis cordyla (Linnaeus) at Vizhinjam

Abstract

The fishery for Megalaspis cordyla (locally called Vangoda) formed on an average 6.63% of the total marine fish landings at Vizhinjam. An increasing trend in the fishery was noticed from 1969 to 1973. Hooks and lines and drift nets contributed to about 95.8% of the catch. Post-monsoon period was the best season for the landings of M. cordyla. Maturity studies indicated that the fish spawned only once a year and the spawning psriod was of prolonged nature, from December to July with intensive spawning during monsoon season. Spawning takes place beyond 5Km fishing belt of Vizhinjam and the probable time of spawning being during night. Both the females and males mature at the minimum size of 250 mm and the size at first maturity being 270 mm. Females were generally found more in the catches. The fish grows to 250 mm in the first year and to 290 mm in second year, 320 mm in the third year and to 330 mm by 40 months. The fishery was composed of 0-year and one-year old fishes, both of them accounting to 90% of the catches, and generally the former being the dominant.